If an element is composed of atoms with an atomic number of 8 and a mass number of 14, then an electrically neutral atom of this element contains
A) 6 protons.
B) 6 neutrons.
C) 6 electrons.
D) 14 protons.
E) 14 electrons.

Question

Quizplus · Accepted Answer

The atomic number of an element is equal to the number of protons in the nucleus of an atom of that element. Thus, if an atom of this element has an atomic number of 8, it has 8 protons. The mass number of an element is the sum of the number of protons and neutrons in the nucleus of an atom of that element. Thus, if an atom of this element has a mass number of 14, it has 8 protons and 6 neutrons. An electrically neutral atom has an equal number of protons and electrons, so it must have 8 electrons. Therefore, the correct choice is B, 6 neutrons.

If an Element Is Composed of Atoms with an Atomic